Preferably vertical air separator

ABSTRACT

A preferably vertical air separator with a rotating separator wheel upon which separating air loaded with fine goods flowing from outside towards the inside impinges, from which said separating air axially flows off through an outlet connection pipe in order to be guided to its further use, e.g. in a filter or the like, said separating wheel being provided with a downstream cover plate and a second cover plate being axially distanced therefrom, and blades being disposed between the two cover plates at their periphery, and the outlet connection delivery end averted from the separating wheel emptying into an outlet chamber the cross section of which is distinctly larger than the cross section of the said outlet connection pipe, so that there occurs an abrupt change of the cross section between the outlet connection pipe and the said outlet chamber.

This application is a divisional of U.S. patent application Ser. No.07/736,209 filed Jul. 26, 1991 to Nied for Preferably Vertical AirSeparator.

This invention relates to an air separator being equipped with aseparator wheel. Such a separator wheel is provided with two coverplates which are kept at a predetermined distance between them while anumber of blades is inserted in the vicinity of the periphery of suchwheel. Such a separator wheel is rotatable around an axle supported inbearings in a stationary housing. The material to be separated consistsof coarse and fine dust particles which are carried along in an air flowand which make up the product stream which is fed into the housing. Thisstream arrives at the separator wheel in radial direction. In the saidwheel, the more coarse dust particles are separated from the air flowand the air flow leaves the said separating wheel in axial directionthrough an outlet pipe and carrying along the fine dust particles. Theair flow carrying the fine dust particles may be guided to a filter inwhich air and fine dust particles are further separated.

A general aspect of the present invention is, to build up such an airseparator with a view to improving the flow conditions in order to saveenergy, to improve the effectiveness as regards separating power, and toallow a compact construction.

It is a particular aspect of the present invention to build an airseparator so that the fine-material stream branched off the productstream by means of the separator wheel until it leaves the separatorhousing will be guided possibly without wear. It is another aspect ofthis invention to be in a position to find easily indications ofunavoidable wear and tear during maintenance of the air separator. Theair separator, therefore, is to be as far as possible resistant to wearand tear and of easy maintenance and repair.

It is a further aspect of this invention to provide for the uniformityof the flow between the two cover plates of the separator wheel in theflow channels which are defined by the two cover plates and the blades.Within the scope of that aspect, the flow velocity is to be modifiedwith respect to the values appearing forcibly if the two cover plates orat least the faces or planes of same facing one another are parallel, asusual with known air separators, for taking into account specialoperating conditions.

It is finally an aspect of this invention to design an air separatorwithin the area of its separating wheel so that losses due to relativemovements between the moving parts and the stationary components areclearly reduced. In doing so, a compact construction of the airseparator is aimed at.

The most essential characteristic features of the invention will resultfrom the patent claims and, in the following, the invention is describedmore in details, taking reference to the accompanying drawings.

In such drawings illustrate

FIG. 1 for explaining, an aspect of the invention, an air separator asused in the invention, in vertical arrangement and as longitudinal,central section, the separator wheel being made in a form as usual todayin general practice,

FIG. 2 an air separator in a representation corresponding to FIG. 1,however in a construction in accordance with this invention, but theseparator wheel still being made as usual in today's general practice,however the outlet pipe for the mixture of separator air and the atleast approximately dust-like solid particles being attributed such asto take into account a partial aspect of this invention although thatattribution be already known as such,

FIG. 3 an air separator wheel in diagrammatic view and as verticalsection, which is made in a form in accordance with one of the aspectsof this invention and which may be used as such both with an airseparator in accordance with FIG. 1 and with an air separator inaccordance with FIG. 2,

FIGS. 4 and 5 Details of the above in enlarged views.

A raw gas flow with coarse and fine solid particles suspended thereinwas fed to a not shown separation plant. The coarse particles areseparated from the raw gas flow and were removed from the separatorhousing. The raw gas flow containing the small particles of low weightreaches the air separator in accordance with FIG. 1 or FIG. 2, however,also those small low-weight particles being different as to their sizeand weight, meaning their "mass".

The air separator as illustrated in FIG. 1 is provided with a separatorwheel which in turn is provided with a first, downstream upper coverplate 1, if the separator is vertically disposed, and with a second,lower cover plate 2, if the separator is vertically disposed, which isaxially displaced with respect to the first one. Blades 3 which areequidistant in circumferential direction are disposed between said twocover plates 1, 2. Separator wheels of that type are known as such sothat it is not necessary to give further explanations as to the shape ofsuch blades. They are firmly disposed along the outer circumference ofthe downstream cover plate and the second cover plate 1, 2 as e.g. saidtwo cover plates are clamped together by bolts and hold the bladesbetween them. Cover plates and blades make up the separator wheelspinning around its longitudinal axis 4. This longitudinal axis 4 maystand vertically as a matter of principle and characterize a standingseparator, but it may also be arranged horizontally characterizing thusa lying separator.

An outlet pipe connection 5 is firmly connected with the downstreamcover plate 1. It extends into the interior of the separator wheel 1through 3 with its section 6 being a dip pipe, in order to be connectedrotationally solidly to the downstream cover plate 1 within theseparator wheel. The inside of the outlet connection pipe is funnel-likeexpanded in an upper section 7 above the cover plate 1; the input andthe outlet flows of the separator air enriched with fine dust andarriving from a separator are designated by the arrows 8, 9. The rotarymotion is transmitted to the separator wheel via the second cover plate2. The relative velocity between the flow and the outlet connection pipe5 in the area of the flow 8, 9 is strongly reduced as compared withconventional solutions.

The separator wheel and the outlet connection pipe 5 coordinatedtherewith are disposed within a casing consisting of a pot-shaped bottompart 10 and an upper lid 11. The two housing parts 10, 11 are placed oneupon the other on peripheral flanges 12, 13 and are detachably connectedwith one another by means of bolts 14 stuck through said peripheralflanges. The bottom part 10 of the casing is provided with a lateralbracket 15 in which the lid 11 is pivoted by means of a pin 16 and istiltable around its longitudinal axis. For tilting said lid 11 aroundthe longitudinal axis of said pin 16, the screwed bolts 14 stuck throughthe flanges 12, 13 are released. The lid 11 is provided with acollar-like attachment 17 in which the outlet connection pipe 5 iscarried rotatably around its longitudinal axis with an upper section 18in the form of a cylindrical tube in two axially distanced bearings 19,20.

The outlet connection pipe is connected, with its upper end, to a notshown source of negative pressure. A driving torque is introduced intothe outlet connection pipe at its upper end, a typical belt pulley 21rotationally solidly connected with the outlet connection pipe and adrive belt 22 acting upon same being shown by way of example outside ofthe upper end of said collar-shaped attachment 17 being detachablyclosed by means of a lid.

The second, the lower cover plate 2 when the air separator is seen invertical build-up, is fixed to a bearing pin 24 by means of a pivot 23,which is carried in bearings 25, 26, rotatably around its longitudinalaxis, in a likewise collar-shaped attachment 27 of the bottom part 10 ofthe housing. The lower cover plate 2 is separately driven, the drivetorque therefor being transmitted to the bearing pin 24 outside of theattachment 27, for the purpose of which, again by way of example, a beltpulley 30 upon which acts a drive belt 31 is rotationally solidly setupon the outer end of the bearing pin 24 outside of the attachment endclosable by means of a detachable lid.

The belt drives 21, 22 on the one hand and 30, 31 on the other areadjusted to one another so that the two cover plates 2, 3 are drivenwith the same number of revolutions or at any other, predetermined speedrelation.

Outside of the said blade ring 3 and concentrically thereto, a guidetube 32 is disposed and is held by means of support vanes 33 in thebottom part 10 of the housing, so that it concentrically surrounds theblade ring 3.

An inlet connection pipe 34 empties radially below the lower, secondcover plate 2 immediately above the bottom face into the bottom part 10of the housing for feeding the separating air. An inlet connection pipe35 empties radially into the bottom 10 of the housing in the area of theguide tube 32 between the cover plates 1, 2 for the goods which are fedinto the housing by means of an inlet scroll 36 disposed in the inletconnection pipe 35.

The separation air enters, while the separation wheel 1 is spinning,through the connection pipe 34, and the goods enter through theconnection pipe 35, into the bottom part 10 of the housing, whereuponthe separating air enriched with goods is led to an elbow 38 in thehousing lid 11 through the ring channel 37 between the guide tube 32 andthe wall of the bottom part 10 of the housing, in which a flow reversaltakes place. The well enriched separating air reaches now the areawithin the guide tube 32 in order to be sucked-in from there into theseparator wheel in radial direction, where the separation from toocoarse-.grain goods is effected at the blades 3, so thatfine-goods-loaded separation air is fed into the separator wheel. Thatfine-goods-loaded separation air is deviated in the separation wheelinto an axial flow direction and is then sucked off by the dip tube 5.In a filter, switched-in downstream of the dip tube section 18, also thefine goods are filtered off the air. The too coarse goods reach the areabelow the second cover plate 2 passing along the second cover plate 2,in order to be further processed from there in an adequate manner.

After folding up the housing lid 11, the interior of the housing 10, 11is easily accessible and cleaning and maintenance, in particular of theair separation wheel part distant from the lower cover plate 2, with theupper cover plate 1 and the blades 3 and, if required, its repair areeasily possible.

Also in case of the air separator as illustrated in FIG. 2, the overallvertical air separator is surrounded by a housing which consistssubstantially of the upper housing part 40 and the lower housing part41. The upper housing part 40 and the lower housing part 41 are providedwith an outwardly directed peripheral flange 42 at the upper or 43 atthe lower rim respectively. The two flanges 42, 43 are placed one uponthe other in the built-in or functional condition of the separator andare fixed one upon the other by suitable means. Such suitable fixingmeans are e.g. bolted connections. Other detachable fixing means may bealso clamps or the like.

At a practically undetermined spot of the flange periphery, the twoflanges are connected to one another by a hinge joint 44 so that theupper housing part 40, after having detached the said flange connectingmeans, may be tilted upward in the direction of the arrow 45 withrespect to the housing lower part 41, so that the housing upper part 40becomes accessible from below and the housing lower part 41 becomesaccessible from above. The housing lower part 41 in turn is made in twopieces and consists substantially of the cylindrical separator spacecasing 46 with the flange 43 at its upper open end and the dischargecone 47 tapering downwards. The discharge cone 47 and the separatorspace casing 46 have mating flanges 48, 49 at their upper or lower endsrespectively, and the two flanges 48, 49 of the discharge cone 47 and ofthe separator space casing 46 are connected by means of detachablefixing means like the flanges 43, 44. The separator casing thus composedis suspended in support arms 50 a plurality of which are distributedpossibly equidistantly around the periphery of the separator casing andengage into the cylindrical separator casing 46.

An essential part of the component parts as incorporated into the airseparator are again the separator wheel with the upper cover plate 1,with the lower cover plate 2 downstream from same and axially distantthereto, and the blades of a suitable contour disposed around the outerperipheries of the two cover plates 1, 2 and firmly connected with sameand equidistantly distributed around the circumference of the separatorwheel. In case of the air separator under consideration here, theseparator wheel is driven via the upper cover plate 1 whereas the lowercover plate 2 is the downstream cover plate.

The support of the air separator wheel comprises a shaft 51 suitablydriven in adequate manner, which extends with its upper part out of theseparator housing and which carries the separator wheel, with its lowerend within the separator housing in a taper bore mounting, and isrotationally solidly connected therewith. The guidance of the separatorwheel shaft 51 extension out of the separator housing is realized by apair of machined plates 52, 53 which close the housing at the upper endof a housing end section 54 tapering upward in the form of a truncatedcone, guide the shaft, and seal that shaft opening without impairing therotational movements of the shaft. The upper plate 53 may suitably beshaped as a flange being rotationally solidly coordinated with the shaft51 and being rotatably supported, by means of pivot bearings, upon thelower plate 52 which on its part is coordinated with the end section 54of the housing. The lower face of the downstream cover plate 2 isdisposed in the common plane between the flanges 43, 44 so that theseparator wheel in its entirety is disposed within the tiltable housingupper part. The housing upper part 40 is additionally provided, in thearea of the conical end section 54, with the product feeding connectionpipe 56 which is a pipe the longitudinal axis of which is disposedparallel with respect to the axis of rotation of the separator wheel andits drive shaft 51 and which is extended as far as possible to theoutside.

The separator housing 46 accommodates the tubular exit connection pipe57 disposed equiaxially with respect to the separator wheel, which isdisposed with its upper end closely below the downstream cover plate 2of the separator wheel, however without being connected to same. At thelower end of the tubular outlet connection pipe, an outlet chamber 58 isequiaxially attached which likewise is tubularly shaped, the diameter ofwhich, however, is substantially larger than the diameter of the saidoutlet connection pipe 57, at least double the diameter of the saidoutlet connection pipe. At the transition between the outlet connectionpipe 57 and the outlet chamber 58 there occurs, therefore, a distinctlyabrupt change of diameters. The outlet connection pipe is inserted intoan upper cover plate 59 of the outlet housing 58, the said outlethousing 58 being closed at its lower end by means of a detachable lid60. The constructional assembly unit consisting of the outlet connectionpipe 57 and the outlet chamber 58 is carried in a plurality of supportarms 61 which are equally distributed around the periphery of the saidconstructional assembly unit in form of a star, are firmly connectedwith the constructional assembly unit in the area of the outletconnection pipe, and are attached, with their other ends, to theseparator housing.

The outlet connection pipe 57 is surrounded by a conical annular casing62 whose lower, larger outer diameter corresponds, at leastapproximately, to the diameter of the outlet chamber, and whose uppersmaller outer diameter corresponds, at least approximately, to thediameter of the separator wheel. The support arms 61 end at the conicalwall of the said annular casing 62 and are firmly connected with saidwall, which in turn is part of the constructional assembly unitconsisting of the outlet connection 57 and the outlet chamber 58.

The support arms 61 and the annular casing 62 are parts of a scavengingair device, said scavenging air preventing matter present in theinterior of the separating casing 46 from penetrating into the gapbetween the separating wheel respectively its lower cover plate 2 andthe outlet connection pipe 57. The support arms are shaped in tubularform in order to guide the said scavenging air into the annular casing62 and from there into the gap to be kept clear, their outer endsections penetrating the wall of the separator casing and beingconnected to a scavenging air source via a suction filter 63. Theannular casing 62 is upwardly closed by means of an orifice plate 64 andthe gap itself can be adjustable by means of an axially settable annulardisk in the area between the orifice plate 64 and the lower cover plate2 of the separator wheel 1, 2, 3.

The outlet from the outlet chamber 58 is constituted by a pipe 65 whichenters the separator casing 46 from outside and is connected to theoutlet chamber 58 in a tangential arrangement. A deflector cone 66 isused for lining the mouth of the fine goods delivery pipe 65 into theoutlet chamber 58.

The separator air intake spiral 67 and the coarse goods delivery end 68are coordinated with the partial casing 47 in horizontal arrangement atthe lower end of the conical partial casing 47. The sense of rotation ofthe separator air intake spiral 67 is opposed to the sense of rotationof the separator wheel. The coarse goods delivery end 68 is detachablycoordinated with the partial casing 47, the lower end of the partialcasing 47 being provided with a flange 69 and the upper end of thecoarse goods delivery end 61 being provided with a flange 70, and bothflanges being detachably connected to one another by known means whenthe separator is operational.

The dispersion zone to be laid out is designated by 71. (Chamfered)flanges machined on the inner edge for a neat guidance of the flow and asimple lining are designated by 72.

Finally, a replaceable shield tube 73 being a wearing part is attachedto the inner wall of the outlet connection pipe 57, and a correspondingreplaceable shield tube 74 may be attached to the inner wall of theoutlet chamber 58.

At the begin of the operation of the separator in the operatingcondition as described, separating air is introduced into the separatorthrough the separating air intake spiral 67 along a pressure head andwith a selected serviceable intake speed. Due to the intake of theseparating air by means of a spiral particularly in connection with theconicalness of the partial casing 47, the separating air spirals upwardinto the area of the separating wheel 1-3. Simultaneously, the "product"consisting of solid particulate matter of varying mass is fed throughthe product input connection pipe 56 into the separator casing. Of thisproduct, the coarse goods, i.e. the particle portion having a heaviermass, arrives in counter flow to the separator air into the area of thecoarse goods delivery end 68 and is made available there for furtherprocessing. The fine goods, i.e. the lower mass particle portion ismixed with the separator air, arrives radially from outside to theinside through the separator wheel into the outlet connection pipe 57,into the outlet chamber 58, and finally through the fine goods deliverypipe 65 into the fine goods delivery end and from there into a filter inwhich the fine goods are separated from the air.

Due to the abrupt cross sectional enlargement between the outletconnection pipe 57 and the outlet chamber 58, there a conspicuousreduction of the flow speed of the fine-goods/air mixture takes place.This mixture arrives at the fine goods delivery end with a very low flowspeed and produces an only low abrasion on its way. For this reason, theshield pipe 74 is a very precautionary measure only. The high flow speedprevailing in the separator wheel necessary there for the reason of agoods separation technique, still prevails however in the outletconnection pipe 57, due to which the shield pipe 73 is to be consideredas being more relevant to the invention. Relevant to the invention isthe abrupt diameter change with a diameter enlargement at the transitionfrom the outlet connection pipe 57 to the outlet chamber 58.

Furthermore, the separator is easy to maintain on account of thesubdivision of the separator housing as above described and thecoordination of the separator components to the various partial casings,and any defective components can be replaced at relatively low costs andwithin short servicing times.

Whereas the separator wheel with the two cover plates 1, 2 and the ringof blades 3 disposed between them is described in the general build-upin accordance with FIGS. 1, 2 in the known, usual form having parallelcover plates with parallel faces, FIG. 3 illustrates the separator wheelfor the air separator according to the invention which is described inthe following taking reference to the build-up of the air separator inaccordance with FIG. 1.

The downstream cover plate 1 remains flat as before and is disposed in aplane which stands perpendicularly with respect to the axis of rotation4 of the separator wheel and the longitudinal axis of the air separator,irrespective of the axis of rotation and longitudinal axis 4 beingvertically or horizontally disposed. It comprises concentrically theoutlet connection pipe 5. The blades 3 extend from said downstream coverplate 1 to the second cover plate. The blades 3 are connected with thetwo cover plates 1, 2. The lower cover plate 2 is, in deviation fromprior art, conically shaped, i.e. preferably in such a manner that thedistance between the second cover plate 2 and the downstream cover plate1 enlarges, preferably continuously, from the blade ring 3 toward theinterior, and again preferably in such a manner that the cross sectionof the channel through which the air flows remains constant for anyradius between the blade trailing edges and the outlet connection pipe5. The outflow velocity reducing due to the reduced radii in case ofknown solutions, remains constant in the solution according to theinvention.

It needs not to be specially explained that the separator wheel 1through 3 may be formed as illustrated in FIG. 3 both in the airseparator build-up in accordance with FIG. 1 and in the air separatorbuild-up in accordance with FIG. 2.

For explaining in further details that the connection between thedownstream cover plate (upper cover plate 1 in FIG. 1 or lower coverplate 2 in FIG. 2) and the outlet connection 18 (FIG. 1) or 20 (FIG. 2)may be made, a FIG. 4 has been added to FIG. 2, which illustrates therespective area in an adequate magnification.

For explaining in further details that the formation of the downflowwith the abrupt diameter change in accordance with FIG. 2 may beprovided also in the air separator in accordance with FIG. 1, a FIG. 5has been added to the FIG. 1, which illustrates the respective area inan adequate magnification.

In relation to the first of the above mentioned three points it is easyto imagin that in case of FIGS. 1 and 3 the separator according to FIG.1 includes the separator wheel in the position shown in FIG. 3 i.e.upper plate 1 of the wheel according to FIG. 3 is the same upper plate 1shown in FIG. 1, whereas in case of FIGS. 2 and 3 the wheel shown inFIG. 3 has to be turned under an angel of 180° to come to the positionas being included in the separator of FIG. 2, i.e. upper plate 1 in FIG.3 is the lower plate in the situation of FIG. 2 and lower plate 2 inFIG. 3 is the upper plate in the position as shown in FIG. 2.

In relation of the second of the above mentioned three points it is easyto understand that chamber 58 and exhaust pipe 57 can be connected tothe wheel 11, i.e. with lower plate 2 of the wheel to be turned togetherwith the wheel, in case between the unit including wheel 11, chamber 58and pipe 57 on the one hand and support arms 61 and pipe 65 on the otherhand there is left a space. In this case in the part of the spacebetween arms 61 and annular casing 62 could be a centering bearing 73(FIG. 4).

In relation to the third of the above mentioned three points, accordingto FIG. 5, which is to be seen in combination with FIG. 1 the outletpipe 6 is followed by a constantly and smoothly widening part 5 and thisis followed by the end part 18 which is getting wider by a step close tothe bearing 20 which means that parts 6 and 5 of the exhaust pipe arefollowed in a step by part 18 which is an equivalent to chamber 58 inFIG. 2.

I claim:
 1. An air separator comprisinga housing having an inlet meansfor receiving an airstream carrying fine particles and an outlet meansfor discharging said airstream, a separator wheel rotatably mounted insaid housing downstream of said inlet means for receiving said airstreamcarrying fine particles and flowing radially inwardly, a downstreamcover plate and a second cover plate mounted on said separator wheel inaxially displaced disposition, a plurality of blades disposedperipherally between the downstream cover plate and second cover plate,an outlet pipe connection means fixedly connected to the downstreamcover plate for rotation therewith, the distance between the downstreamcover plate and the second cover plate increasing from the outside edgesof the blades toward the outlet pipe connection inversely with distancebetween the blades, so that the cross sectional area of the channeldefined by the blades, the douwnstream cover plate and the second coverplate remains substantially constant, said outlet means being downstreamof said outlet pipe connection means for discharging said airstream fromsaid housing.
 2. An air separator in accordance with claim 1, furthercomprising an outlet connection pipe mounted on the outlet pipeconnection means and having a section with a cross sectional area whichincreases with distance from the downstream cover plate.
 3. An airseparator in accordance with claim 2, further comprising means formingan outlet chamber mounted on the outlet pipe, said outlet chamber havinga cross section substantially larger than the maximum cross section ofthe outlet pipe so that there occurs an abrupt change of the crosssection between the outlet connection pipe and the outlet chamber.
 4. Anair separator in accordance with claim 1 wherein the distance betweenthe downstream cover plate and the second cover plate increases linearlywith radial distance from the outside edges of the blades.
 5. An airseparator in accordance with claim 4, wherein the rate of increase indistance remains constant along any radius between the outside edges ofthe blades and the outlet connection pipe.